Interferon-alpha 1a (IFN-alpha 1a) is a leukocyte interferon, which is a variant of Interferon-alpha. IFN-alpha 1a is a 19.5kDa protein containing 167 amino acid residues. It could bind the interferon receptors that activates the signal transduction of immune responses through the Jak/STAT pathway in leukocytes and lymphoblastoid cells.